Sound card reccomendations?

[backdoorbobby]

Hey guys, I'm wanting to give my brother a fairly good set up for recording on linux for his 21st birthday. He currently uses his 2011 imac and uses firewire input. I can obtain a computer with decent specs (2.5ghz dual processor, 4gb ram, etc. but I'd imagine I would need to purchase a higher end sound card to record quality music and use his firewire input. So my question is, does anybody recommend a sound card that is compatible with a good distro for recording music? Any suggestions or corrections would be greatly appreciated.
Thanks in advance for any replies.